On-Demand Mobile CPU Cooling With Thin-Film Thermoelectric Array

On-demand cooling is inevitable to maximize the processor’s performance, while fulfilling thermal constraints—this holds more in advanced technologies, where localized hotspots change during runtime. In this work, we propose to adopt an array of thin-film thermoelectric (TE) devices, which is integrated within the chip packaging, for both cooling and energy-harvesting purposes. Each TE device within the array can be during the runtime enabled either for energy harvesting or on-demand cooling. Our approach is implemented and evaluated using a mature finite elements analysis tool in which a commercial multicore mobile chip is modeled after careful calibrations together with state-of-the-art TE devices. Results demonstrate that our approach reduces the peak temperature by up to 24 ^\circ C∘C and the average temperature by 10 ^\circ C∘C across various benchmarks with the cost of 67.5 mW. Additionally, the harvested energy from the array of TE devices compensates for 89% of the required cooling energy.